String
• Belongs to the System namespace.
• Immutable i.e. whenever you append a String object it creates a new object with new memory allocation.
• When changed, a new object is created and old object is destroyed.
• Avoid using inside loops, as if the loop executes N times. N memory allocation operations will be performed.
• Concat function is used for String concatenation.
Example:
string s = "Jack";
s = string.Concat(s, "Mike");
StringBuilder
• Belongs to the System.Text namespace.
• Mutable i.e. whenever you append a String object it does not creates a new object with new memory allocation.
• When changed, no new object is created or old object is destroyed.
• Recommended for loops, as only the size of object will change.
• Append function is used for String concatenation.
Example:
StringBuilder sb = new StringBuilder();
sb.Append("Jack");
sb.Append("Mike");
